In conventional liquid-crystal displays (TN, STN, OMI or AMD-TN), the electric fields for realignment are generated essentially perpendicular to the liquid-crystal layer.
International Patent Application WO 91/10936 discloses a liquid-crystal display in which the electric signals are generated in such a way that the electric fields have a significant component parallel to the liquid-crystal layer (IPS, in-plane switching). The principles of operating such a display are described, for example, by R. A. Soref in Journal of Applied Physics, vol. 45, No. 12, pp. 5466-5468 (1974).
EP 0 588 568 discloses various ways of addressing a display of this type.
These IPS displays can be operated with liquid-crystalline materials either of positive or of negative dielectric anisotropy (.DELTA..epsilon..noteq.0). However, using the materials known hitherto, relatively high threshold voltages and long response times are reached in IPS displays.